1. Field of the Invention
This invention relates to water-absorbent coating compositions to be applied to wall covering materials required to prevent dew condensation or to be wettable with water, and to a coating process using the same.
2. Description of the Background Art
Conventional water-absorbent coating compositions, known as dew-condensation preventing paint, comprise a polymer emulsion, a polymer solution, and a porous, water-absorbent pigment ( such as calcium carbonate, diatomaceous earth, vermiculite and perlite ) or a water-absorbent resin.
Those containing water-absorbent pigment have to be coated to a relatively large thickness. Those containing a water-absorbent resin, which is a powder not smaller than several tens of microns in size, also have to be coated to a relatively large thickness, and the coated film is poor in surface smoothness; in addition, the manufacturing process involves a special step for dispersing the powder of resin.